Chemically combined​
Answer:
A compound
Explanation:
A compound is a substance made up of two or more components that are chemically combined together.
The substances that combines to form a compound is called elements.
The properties of compounds are distinct and different from the elements that combines to make them.
A wide array of compounds are known and they arise from different arrangements of atoms of elements.
The tying results in the more visible veins of upper arms due to blood flow restriction.
Veins are the part of circulatory system in the body, that functions to carry deoxygenated blood from different parts of the body to the heart.
The venipuncture has been the process of insertion of drugs or chemicals in a body through vein. The veins of the upper arm has been tied to make them more visible.
The upper arm veins are more visible as there has been blood flow restriction in the veins by tying that results in the bulging out of the vein.
For more information about veins, refer to the link: